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Scientists plan to freeze ship in Arctic ice to understand melt

An international expedition to the Arctic will intentionally freeze a ship into the ice for a year so scientists can monitor the pace at which the ice is disappearing.

For decades, scientists have been using satellite images and other data to measure the steadily declining area of summer ice cover over the Arctic ocean and how it’s been disappearing at a rate of around 12 per cent per decade since 1979. The big question is how long do we have before it is gone completely?

Beginning next September, researchers from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Germany will embark on the largest expedition in history to the Arctic to try and answer that question. The international project, called MOSAiC, involving 17 countries and 600 scientists, will intentionally trap a ship in the ice for a year to follow its movement.

Circulation of Arctic ice is shifting

Unlike the ice cover in a lake, which remains fixed over the winter, ice in the Arctic Ocean is constantly circulating in a clockwise direction from Siberia, across Greenland, Northern Canada and back again. Along the way, some of it ages and becomes permanent pack ice that can remain for years, while other ice eventually flows south into the Atlantic along the coasts of Greenland.

A recent report from the institute has shown that one source of new ice in Siberia is faltering, so it is melting before it completes the entire journey. This means that not only is there less ice, but the ice that is there is thinner. And thin ice melts faster.

The MOSAiC mission will embed the German research icebreaker Polarstern into the drifting ice. That will carry it around the Arctic, which is otherwise virtually inaccessible in the winter. The ship will act as a base for a network of scientific observation posts that will attempt to better understand the dynamics of the ice in real time and to get a better estimate on how soon the Arctic Ocean will be completely ice-free during the summer.

Implications of less Arctic ice

That turning point, which could arrive suddenly, will accelerate climate change as the dark ocean absorbs more sunlight than white ice. A warmer North will increase permafrost melt, which releases methane, another greenhouse gas. Weather patterns and ocean currents could change, affecting not only people and animals in the North, but also regions to the south. As we saw this week from a report by Environment and Climate Change Canada, those effects are already happening as our country warms faster than the rest of the planet. When the ice is gone, change could come even faster.

Disappearing ice is even having an effect at the microscopic level as nutrients and algae that are normally transported from shallow waters to the deep on drifting ice will no longer have that transarctic conveyor belt, changing the productivity of the Arctic Ocean and possibly the life within it.

Of course, not all the news is bad. Shipping companies, tour operators and resource extraction will all benefit from the open waters. The big question is, how will we adapt to a warmer world?

A new look for the Arctic

To climate scientists, who have been waving this red flag for decades, the slow pace of reducing carbon emissions has been frustrating. That is partly due to the fact that the most dramatic changes are happening in remote regions. It is easy to be in denial about climate change because we in the south are still enjoying fair weather. In fact, after this brutal winter, many Canadians would welcome a warmer climate. But the North is a ticking time bomb of change.

Disappearing ice is like a receding hairline for the planet. As long as there is still some white up there, the frozen North still looks frozen. But the white is thinning, and we can only get away with a comb-over for so long. In the same way a person’s face changes instantly when they finally allow the baldness to show, the baldness at the top of the world will dramatically change the face of the planet.

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Fonte
CBC

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